Spritz the fish pieces all over with olive oil spray. Season them evenly with Cajun seasoning. Cut one lime into wedges and halve the other lime for juice and garnish.

In a small bowl, combine the mayonnaise, sriracha (or chipotle sauce), and juice of 1/4 lime. Add a little water, a teaspoon at a time, until the sauce is thin enough to drizzle easily over the fish later.

Place the seasoned fish pieces in the air fryer basket. Air fry at 400°F for 6 minutes, shaking the basket halfway through the cooking time. Alternatively, heat a skillet over high heat, lightly spray with olive oil, and cook the fish pieces for 5 to 6 minutes until cooked through.

While the fish cooks, toss the slaw mix with 1/2 tablespoon olive oil, juice from 1/2 lime, and 1/2 teaspoon kosher salt. Mix well to combine.

Divide the slaw evenly onto 4 plates. Arrange the cooked fish pieces on the side. Drizzle the spicy mayo over the fish generously.

Garnish with lime wedges and chopped cilantro if desired. Serve immediately for the best flavor and texture.